That being said, *if* you care *and* it is really NBD to you, you might consider doing it and demonstrating your commitment to supporting S2's relationship with that side of his family. (Also, it might be nice for S2 to participate in his cousin's BD party-- is that why they can't come get him?) Maybe there is something close to her house that would be a fun excursion for you to do on your own or earlier in the day with S2, a hike or a beach or something? Possibly could be viewed as a good excuse to get out and do something different.
If I were you I'd also be weighing COVID questions, and maybe a birthday party isn't a great idea.
Anyway, I'm sure you'll make the right choice!
Me (46) H (42) M:14 T:18, D9 & D11 4/19 - 12/19: series of escalating BDs 9/20 - present: R and piecing
